diff --git a/src/cocoa_init.m b/src/cocoa_init.m
index 7c208b90..3bb61c18 100644
--- a/src/cocoa_init.m
+++ b/src/cocoa_init.m
@@ -103,6 +103,9 @@ int _glfwPlatformInit(void)
 
     _glfwInitJoysticks();
 
+    if (!_glfwInitOpenGL())
+        return GL_FALSE;
+
     _glfwLibrary.NS.eventSource = CGEventSourceCreate(kCGEventSourceStateHIDSystemState);
     if (!_glfwLibrary.NS.eventSource)
         return GL_FALSE;
@@ -143,6 +146,8 @@ int _glfwPlatformTerminate(void)
 
     _glfwTerminateJoysticks();
 
+    _glfwTerminateOpenGL();
+
     return GL_TRUE;
 }
 
diff --git a/src/cocoa_opengl.m b/src/cocoa_opengl.m
index 1f1f0f23..4d4c4299 100644
--- a/src/cocoa_opengl.m
+++ b/src/cocoa_opengl.m
@@ -29,18 +29,46 @@
 
 #include "internal.h"
 
+#include <pthread.h>
+
 
 //========================================================================
 // The per-thread current context/window pointer
-// TODO: Implement pthreads TLS
 //========================================================================
-_GLFWwindow* _glfwCurrentWindow = NULL;
+static pthread_key_t _glfwCurrentTLS;
 
 
 //////////////////////////////////////////////////////////////////////////
 //////                       GLFW platform API                      //////
 //////////////////////////////////////////////////////////////////////////
 
+//========================================================================
+// Initialize OpenGL support
+//========================================================================
+
+int _glfwInitOpenGL(void)
+{
+    if (pthread_key_create(&_glfwCurrentTLS, NULL) != 0)
+    {
+        _glfwSetError(GLFW_PLATFORM_ERROR,
+                      "Cocoa/NSGL: Failed to create context TLS");
+        return GL_FALSE;
+    }
+
+    return GL_TRUE;
+}
+
+
+//========================================================================
+// Terminate OpenGL support
+//========================================================================
+
+void _glfwTerminateOpenGL(void)
+{
+    pthread_key_delete(_glfwCurrentTLS);
+}
+
+
 //========================================================================
 // Make the OpenGL context associated with the specified window current
 //========================================================================
@@ -52,7 +80,7 @@ void _glfwPlatformMakeContextCurrent(_GLFWwindow* window)
     else
         [NSOpenGLContext clearCurrentContext];
 
-    _glfwCurrentWindow = window;
+    pthread_setspecific(_glfwCurrentTLS, window);
 }
 
 
@@ -62,7 +90,7 @@ void _glfwPlatformMakeContextCurrent(_GLFWwindow* window)
 
 _GLFWwindow* _glfwPlatformGetCurrentContext(void)
 {
-    return _glfwCurrentWindow;
+    return (_GLFWwindow*) pthread_getspecific(_glfwCurrentTLS);
 }
 
 
@@ -83,7 +111,7 @@ void _glfwPlatformSwapBuffers(_GLFWwindow* window)
 
 void _glfwPlatformSwapInterval(int interval)
 {
-    _GLFWwindow* window = _glfwCurrentWindow;
+    _GLFWwindow* window = _glfwPlatformGetCurrentContext();
 
     GLint sync = interval;
     [window->NSGL.context setValues:&sync forParameter:NSOpenGLCPSwapInterval];
diff --git a/src/cocoa_platform.h b/src/cocoa_platform.h
index 97e903d7..a202c25e 100644
--- a/src/cocoa_platform.h
+++ b/src/cocoa_platform.h
@@ -124,4 +124,8 @@ void _glfwTerminateJoysticks(void);
 GLboolean _glfwSetVideoMode(int* width, int* height, int* bpp, int* refreshRate);
 void _glfwRestoreVideoMode(void);
 
+// OpenGL support
+int _glfwInitOpenGL(void);
+void _glfwTerminateOpenGL(void);
+
 #endif // _platform_h_
diff --git a/src/win32_opengl.c b/src/win32_opengl.c
index fb0ba47f..6801e144 100644
--- a/src/win32_opengl.c
+++ b/src/win32_opengl.c
@@ -33,10 +33,22 @@
 #include <stdlib.h>
 
 
+//========================================================================
+// Thread local storage attribute macro
+//========================================================================
+#if defined(_MSC_VER)
+ #define _GLFW_TLS __declspec(thread)
+#elif defined(__GNUC__)
+ #define _GLFW_TLS __thread
+#else
+ #define _GLFW_TLS
+#endif
+
+
 //========================================================================
 // The per-thread current context/window pointer
 //========================================================================
-__declspec(thread) _GLFWwindow* _glfwCurrentWindow = NULL;
+static _GLFW_TLS _GLFWwindow* _glfwCurrentWindow = NULL;
 
 
 //========================================================================
diff --git a/src/x11_opengl.c b/src/x11_opengl.c
index d7f33999..38a43ff0 100644
--- a/src/x11_opengl.c
+++ b/src/x11_opengl.c
@@ -37,10 +37,21 @@
 // This is the only glXGetProcAddress variant not declared by glxext.h
 void (*glXGetProcAddressEXT(const GLubyte* procName))();
 
+
+//========================================================================
+// Thread local storage attribute macro
+//========================================================================
+#if defined(__GNUC__)
+ #define _GLFW_TLS __thread
+#else
+ #define _GLFW_TLS
+#endif
+
+
 //========================================================================
 // The per-thread current context/window pointer
 //========================================================================
-__thread _GLFWwindow* _glfwCurrentWindow = NULL;
+static _GLFW_TLS _GLFWwindow* _glfwCurrentWindow = NULL;
 
 
 //========================================================================